File photo: During a private luncheon Wednesday, Sen. Lindsey Graham, R-S.C., exploded at Sen. Bob Corker, R-Tenn., a frequent Trump critic, according to several people familiar with the exchange. One person who witnessed the encounter said Graham accused Corker of trying to destroy the Republican Party as Corker heads toward retirement.

WASHINGTON – The normally decorous Senate has been rocked by heated confrontations this week as fellow Republicans have traded personal and profane insults over how much loyalty to show President Donald Trump.

As Trump asserts his dominance of the party, a vocal GOP minority is speaking out against him – and antagonizing other Republicans who are trying to forge a lasting relationship with the president to achieve their political and legislative goals.

During a private luncheon Wednesday, Sen. Lindsey Graham, R-S.C., exploded at Sen. Bob Corker, R-Tenn., a frequent Trump critic, according to several people familiar with the exchange. One person who witnessed the encounter said Graham accused Corker of trying to destroy the Republican Party as Corker heads toward retirement.

Corker’s portrayal of his colleagues’ support for Trump as “cult-ish” has bothered Graham and other senators.

“I’ve always been a fan of Bob. I think he’s very, very smart,” Graham said Thursday. “But at the end of the day we’re not helping here to suggest that somehow the Republican Party is a cult.”

Graham also clashed with Republican Sens. Mike Lee, Utah, and Rand Paul, Ky. Their disputes have centered on amendments to an annual defense bill – raising the temperature even more in a legislative chamber known for its cordiality.

The flashes of anger underscore the Republican Party’s turbulent state less than five months before midterm elections that threaten to wipe away its congressional majorities. Intraparty tension has been evident all week across the country as Trump tightens his grip on the GOP and Republicans abandon long-held principles on trade and national security to align with the president’s policies.

South Carolina Rep. Mark Sanford’s ouster in a Republican primary Tuesday was a harsh reminder of the perils of crossing Trump and a new incentive for incumbents to stick with the president. In the Capitol on Thursday, the Senate sided with the Trump administration to vote down a GOP plan that would have given Congress greater oversight over deals between foreign and U.S. firms.

The level of Republican loyalty to Trump has troubled Corker and Sen. Jeff Flake, R-Ariz., both of whom are retiring at the end of the year. As Republicans held the luncheon Wednesday where Graham fought with Corker and Lee, Flake was on the Senate floor delivering a speech criticizing Trump’s embrace of “despots and dictators” while “ridiculing our allies.”

“We continue to act here as if all is normal, as if all parties are observing norms,” Flake said. “Even as the executive branch shatters them.”

Graham launched into an expletive-laced attack on Corker during the lunch as their colleagues looked on, people familiar with the discussion said. Graham pointed out that Corker was retiring, and he argued that the Tennessean was hurting the party.

“You’re trying to destroy the Republican Party,” the person who witnessed the exchange recalled him saying. Like others interviewed, this person spoke on the condition of anonymity to discuss private talks.

By the end of the lunch, the temperatures had clearly cooled, according to senators who attended, and Graham had apologized to Corker. But the fierce back-and-forth was not forgotten by their colleagues.

“You ought to get ’em together and give ’em a gun, you know?” quipped Sen. Richard Shelby, R-Ala.

Graham declined to talk Thursday about what he said in the lunch. Corker sought to play down the friction and said the outcome was positive. “It all ended great. It really was. It was a great meeting. One of the best meetings we’ve had,” he said.

Corker had delivered a fiery Senate floor speech Tuesday mocking his colleagues for being afraid to “poke the bear” and challenge the president by voting on an amendment to grant Congress more authority over tariffs.

During that speech, Corker called out a senior GOP senator in an unusually personal fashion. Referring to Senate Majority Whip John Cornyn, R-Texas, Corker said: “I heard the senator from Texas, the senior senator from Texas, saying the other day, ‘Well, gosh, we might upset the president. We might upset the president of the United States before the midterms.’ ”

Asked about that comment, Cornyn declined to respond. “I’m not going to engage,” he said. “He’s entitled to his point of view, I just disagree with it.”

Also during the Wednesday lunch, Graham, a Republican national security hawk, took issue with an amendment to the annual defense bill Lee was pushing. The provision was designed to protect Americans from detention without charge or trial.

According to the person who attended the lunch, Graham accused Lee of pressing for the amendment to raise money, prompting the normally polite and low-key senator to snap back.

“Like hell I’m doing that!” Lee responded. “That is one of the most uncollegial and inappropriate arguments I’ve ever heard, and I will not tolerate that.”

Graham later apologized to Lee, and Lee accepted. The Mormon senator told Graham that if he drank beer, he would take him out for one.

“It was unusual to see Lindsey so worked up, because he’s seen a lot and he rolls with the punches,” said one Republican senator, who spoke on the condition of anonymity to describe the private gathering.

At one point during the lunch, Sen. Ted Cruz, R-Texas, who spent most of his first term as a thorn in the side of many of his Republican colleagues, tried to intervene and broker a solution to one of the disputes, according to multiple people who attended the lunch or were briefed on it.

The tense lunch underscored another long-simmering irritation in the Senate this year: a legislative chamber that had yet to do much legislating, with few votes on amendments taken so far this year.

“People want to be able to get votes on amendments,” Cornyn said. If “people can’t get votes on amendments because other Republicans object to it, then it’s a very frustrating outcome.”

The closed-door lunch had started with a discussion about rescission – the process of paring back previously allocated government spending – and featured White House budget director Mick Mulvaney.

"There is a general recognition that we don't need these military-style weapons in New Zealand, so it's very easy to win cross-party support for this," said Mark Mitchell, who was defense minister in the previous, center-right government and who supports the ban initiated by the center-left-led Labour Party.